This Buffer is used in the regular length AR-15 buffer tube that enables the longer .308 bolt group to function normally without the need of adding a longer buffer tube to the stock assembly if the buffer tube spring is shortened or replaced with the shorter LR.308 spring. Its heavier weight allows reduced recoil, working very well in most applications.

Purchased these as spares for my AR-10, have not used them as yet. Good quality and construction